Search

Konjac glucomannan (KGM) is a herbal medicine with benefits in appetite control, body weight and biochemical parameters in overweight individuals. The objective of our work was to evaluate the effect of the consumption of gummy candy enriched with KGM on appetite, to evaluate anthropometric data, biochemical and oxidative stress markers in overweight individuals. Forty-two participants aged 18 to 45 years completed our randomized, double-blind, placebo-controlled clinical trial. Participants were randomly assigned to consume for fourteen days, 2 candies per day, containing 250 mg of KGM or identical-looking placebo candy with 250 mg of flaxseed meal, shortly after breakfast and dinner. As a result, we observed that there was a reduction in waist circumference and in the intensity of hunger/satisfaction of the participants who consumed KGM for fourteen days, and we believe that a longer consumption time as well as an increase dose of KGM contribute to even more satisfactory body results.

Antioxidants are an alternative to prevent or retard biodiesel degradation. Soursop (Annona muricata L.) is a native tropical fruit with important antioxidant activity, besides high concentration of phenolic compounds. Peels form about 20 % of the soursop fruit composition and are usually discarded as a waste product. In this study the antioxidant potential of different peel extracts was evaluated by oxidative stability when used as an additive into soybean biodiesel. All samples were analyzed by the Rancimat® 873, using 32 experimental design. The tests were performed with biodiesel B100 with solutions extracted in different conditions, such as pH and residue concentrations. Results demonstrated that all experiments were able to increase significantly the induction period (IP), when compared to a pure biodiesel control sample, and showed similar efficiency with synthetic antioxidants (BHT). Among all experiments, each neutral and alkaline extractions presented induction periods over 8 h, achieving and surpassing the minimum allowed by European standard. However, the highest IP was found to be 10.30 h, with 3 g L-1 in neutral extraction. Results corroborate that soursop peel has a high antioxidant capacity and efficiency to improve the oxidation stability, and could be used as an inexpensive natural antioxidant to biodiesel.

Introduction: Acquired Immunodeficiency Syndrome (AIDS) is a disease of the human immune system resulting from infection by the Human Immunodeficiency Virus (HIV) virus. Methods: The study was carried out between 2015 and 2016 with patients who attended a Specialized Center for Parasitic Infectious Diseases in Paraná. The research was divided into two stages, where the effects of supplementation on TC4 + cells, viral load (LV) and number of opportunistic diseases were verified. 20mg / day of zinc was added to the cookies for 3 months. Results: Data analysis does not show statistical differences in VL and Zinc supplementation; however, supplementation shows that it is able to promote an increase in the TCD4 + count. Patients reported an improvement in their well-being and a decrease in the incidence of opportunistic diseases. Conclusion: Thus, it was observed that zinc supplementation was highly effective in increasing TCD4 + positively improving the immune response and quality of life. In addition, the supplementation in the form of biscuits proved to be innovative and very effective.

Different ingredients and adjuncts have been used in the production of craft beer aiming to add new characteristics to the final product. In turn, the pecan nut has recognized antioxidant properties and, therefore, the extract of its shell was added in the beer production process with the main objective of increasing the beer antioxidant capacity. The all-grain method was used to produce the beverage and, on the packaging step, pecan nutshell extract was added at three different concentrations. The samples underwent antioxidant, physicochemical, and sensorial analysis. Data were submitted to analysis of variance (ANOVA). The use of pecan nutshell extract as an ingredient in beer processing has proved to be a viable alternative due to satisfactory results in sensory evaluation, with good acceptability of the consumers, maintaining physicochemical characteristics similar to the standard beer produced without the extract. However, the addition of the extract did not increase the antioxidant capacity in craft beer. Even though the antioxidant power of produced beer wasn´t increased in this experiment, still pecan nutshell could be a good resource of antioxidants to whom drink beer, and your low price in the market make it viable to beer industry.

This study aimed to evaluate the antimicrobial activity of clove (Syzygium aromaticum), citronella (Cymbopogon winteranius) and melaleuca (Melaleuca alternifolia) essential oils (EOs) on CoPS. Of the 67 cerumen samples collected, 17 CoPS strains were isolated. Using the microdilution method in a 96-well plate, EOs were added at a maximum concentration of 10% and minimum of 0.04%. It is concluded that the EOs of clove and citronella demonstrate antimicrobial activity against strains of CoPS isolated from canine external otitis. At the concentrations used, melaleuca essential oil did not show any bacteriostatic or bactericidal effects.

Devido a composicao quimica, o biodiesel e muito suscetivel a oxidacao, tornando necessaria a adicao de antioxidantes que inibem ou retardam esse processo. Entretanto os antioxidantes ficam expostos a condicoes que podem degrada-los, reduzindo sua eficiencia. Dessa forma, o uso de nanoesferas (NE) surge como alternativa para proporcionar a protecao dos mesmos. Neste sentido, o objetivo deste trabalho foi desenvolver NE de poli-ɛ-caprolactona contendo o antioxidante terc-butil-hidroquinona e aplica-las no biodiesel. O metodo utilizado na producao das NE foi emulsificacao-evaporacao do solvente e a estabilidade foi avaliada durante 31 dias na estufa a 30°C, sendo analisados o tamanho, polidispersao, potencial zeta, atividade antioxidante e pH durante o periodo estudado, alem da avaliacao do tempo de inducao do biodiesel contendo as NE. Apos o periodo analisado, as NE sofreram variacoes estatisticamente significativas no pH (6,20 para 7,63), potencial zeta (-12,50 mV para -13,83 mV) e a atividade antioxidante (84,4 para 51%). Quanto ao TI, a adicao das NE ao biodiesel nao resultou em variacoes significativas.

This study results from a systematic review to investigate the possible relationship between pesticide exposure and the induction of body overweight in adult individuals. We used the PICO strategy (Population, Interventions/exposure, Comparisons, Outcomes) and the PUBMED, SCIENCE DIRECT and SCOPUS databases to perform the research. In this review, were included 15 studies, classified as research articles. The data presented demonstrated that 86.66% (13/15) of the studies positively correlated overweight and pesticide exposure. Additionally, we observed exposure to pesticides regarding deregulation mechanism of glucose (increase levels of glucose, insulin and homeostasis model assessment insulin resistance index (HOMA-IR)) and deregulation lipid homeostasis (increase levels of triglycerides and decreased levels of high-density lipoprotein (HDL)). These findings proposed an increase in the risk of cardiac diseases and diabetes. As well, these results show that exposure to pesticides can also increase the risk of overweight development. However, further studies are needed to determine the possible mechanism. Este estudio es el resultado de una revisión sistemática para investigar la posible relación entre la exposición a plaguicidas y la inducción del sobrepeso corporal en individuos adultos. Se utilizó la estrategia PICO (Population, Interventions/exposure, Comparisons, Outcomes) y las bases de datos PUBMED, SCIENCE DIRECT y SCOPUS para realizar la búsqueda. En esta revisión, se incluyeron 15 estudios. Los datos presentados demostraron que el 86,66% (13/15) de los estudios correlacionaron positivamente el sobrepeso y la exposición a plaguicidas. Además, se observó que la exposición a plaguicidas afectaba al mecanismo de desregulación de la glucosa (aumento de los niveles de glucosa, insulina e índice de resistencia a la insulina del modelo de homeostasis (HOMA-IR)) y a la desregulación de la homeostasis de los lípidos (aumento de los niveles de triglicéridos y disminución de los niveles de lipoproteínas de alta densidad (HDL)). Estos resultados proponen un aumento del riesgo de enfermedades cardíacas y de diabetes. Además, estos resultados muestran que la exposición a los pesticidas también puede aumentar el riesgo de desarrollar sobrepeso. Sin embargo, se necesitan más estudios para determinar el posible mecanismo. Este estudo resulta de uma revisão sistemática com objetivo de investigar a possível relação entre a exposição a agrotóxicos e a indução de excesso de peso corporal em indivíduos adultos. Utilizou-se a estratégia PICO (Population, Interventions/exposição, Comparisons, Outcomes) e as bases de dados PUBMED, SCIENCE DIRECT e SCOPUS para realizar a busca. Nesta revisão, foram incluídos 15 estudos. Os dados apresentados demonstraram que 86,66% (13/15) dos estudos correlacionaram positivamente o excesso de peso e a exposição a agrotóxicos. Além disso, observamos relação entre a exposição aos agrotóxicos e o mecanismo de desregulação da glicose (aumento dos níveis de glicose, insulina e índice de resistência à insulina de avaliação do modelo de homeostase (HOMA-IR)) e desregulação da homeostase lipídica (aumento dos níveis de triglicerídeos e diminuição dos níveis de lipoproteína de alta densidade (HDL)). Esses achados propuseram um aumento no risco de doenças cardíacas e diabetes. Além disso, esses resultados mostram que a exposição a agrotóxicos também pode aumentar o risco de desenvolvimento de excesso de peso. No entanto, mais estudos são necessários para determinar o possível mecanismo.

Biodiesel is subject to radical reactions that promote degradation. To decrease the speed of these degradation reactions and increase oxidative stability, either natural or synthetic antioxidants are added to biodiesel. Thus, the objective of this study is to evaluate the effect of extracts of pecan nutshell (Carya illinoensis) as natural antioxidants derived from biomass using water, ethanol, and methanol/water (50/50) as a solvent for extraction. The addition of these antioxidants is performed during the soybean biodiesel washing process in an unconventional manner. The results obtained are statistically analyzed and compared to the control. The induction time (IT) for the biodiesel samples washed with ethanolic extract of pecan nutshell (5 g L−1), aqueous extract of pecan nutshell (12 g L−1) and methanol/water extract of pecan nutshell (12 g L−1), are, respectively, 9.46, 7.60, 7.43 h. The activation energy and the storage time of the biodiesel samples washed with the extracts are also studied. The order of reaction of the oxidation kinetics of biodiesel is first order.

RESUMO Os incentivos às políticas energéticas e as atuais exigências ambientais motivam a busca por fontes de energia alternativa, como o gás hidrogênio. Este trabalho tem como objetivo a produção do gás hidrogênio via eletrólise do ácido fórmico, utilizando eletrodos de aço carbono 1008 e ferro Armco. Os ensaios foram feitos mediante planejamento experimental, e empregaram-se as técnicas de microscopia óptica, polarização potenciodinâmica catódica, potencial de circuito aberto e cronoamperometria. Os resultados mostraram que o tratamento da superfície dos eletrodos com lixa de carbeto silício (SiC) #320 é eficiente quando comparada aos outros tratamentos testados, para o desprendimento de H2. O ferro Armco, apresentou maior produção de hidrogênio, em média 70% a mais quando comparado com a platina em ambos os meios estudados, entretanto sua vida útil é menor. ABSTRACT Incentives for energy policies and current environmental requirements motivate the search for alternative energy sources such as hydrogen gas. This paper aims at the production of hydrogen gas via electrolysis of formic acid using electrodes of 1008 carbon steel and Armco iron. Samples were done by experimental design, and employed the techniques of optical microscopy, cathodic potentiodynamic polarization, open circuit potential and chronoamperometry. The results showed that the surface treatment of the electrodes with #320 grit SiC abrasive paper is effective when compared to the other treatments tested for the evolution of H2. The Armco iron, showed higher hydrogen production, on average 70% increased when compared with platinum in both studied media, however its lifetime is shorter.

Os problemas ambientais causados pelo uso de combustiveis fosseis e a necessidade de um novo caminho baseado em fontes energeticas renovaveis impulsionam o desenvolvimento de combustiveis produzidos a partir da biomassa. Os biocombustiveis sao considerados uma opcao estrategica para a geracao de energia, entre eles destaca-se o etanol. Visando minimizar a competicao com a cadeia alimentar, as fontes amilaceas sao alternativas para obtencao do biocombustivel, entre elas a Cyperus esculentus (CE). Este trabalho teve como objetivo estudar as condicoes ideias para a obtencao de etanol a partir da fermentacao da farinha de CE, utilizando a rota enzimatica para a reacao de hidrolise. Foi utilizado planejamento fatorial (3²), a fim de verificar a influencia das variaveis independentes: tempo de fermentacao (h) e concentracao de levedura (g L -1 ) para a rota enzimatica em relacao a resposta grau alcoolico (°GL). Para caracterizacao da materia-prima foram realizados ensaios de determinacao de teor de umidade, teor de amido, acucares redutores (AR), analise quimica elementar e microscopia eletronica de varredura (MEV). Apos a fermentacao, foram realizadas medidas de UV-vis para determinacao do °GL. As amostras apresentaram valores de teor de umidade de 55,05%, teor de amido de 52,38% e de AR de 12,23%. As imagens de MEV mostraram elementos de protoxilema e protofloema. Com o planejamento fatorial alcancou-se as condicoes ideais ( 15 g L -1 para concentracao de levedura e 30 h para o tempo de fermentacao) para obtencao de etanol com teor alcoolico de 24,27 °GL.

Corrosion is an undesirable action which can occur in metals. To minimize this problem, there are several types of coat to the metal surface being researched in an attempt to retard the oxidation processes. In this work, the deposition of a new ceramic coating based on niobium oxide over aluminum alloy AA 3003 was studied in order to obtaining a corrosion resistant and less polluting film. It was utilized the experimental planning to optimize the deposition of ceramics, and it was performed electrochemical tests, scanning electron microscopy and dispersive energy spectroscopy to evaluate these films. The ceramic coating based on niobium oxide obtained presented itself as an effective corrosion inhibitor for aluminum alloy AA 3003.

A cromagem é uma opção que a indústria de metal mecânica tem encontrado para aumentar a resistência à corrosão de peças metálicas, porém esse revestimento apresenta a desvantagem de ser tóxico ao ser humano e ao meio ambiente. Para se alcançar um novo tratamento de superfície, pode-se aplicar planejamento experimental, a fim de otimizar os experimentos, principalmente quando há diversas variáveis para se chegar ao processo ou produto final. O objetivo principal deste trabalho é utilizar planejamento experimental para se obter um revestimento cerâmico à base de óxido de nióbio para ligas de alumínio 3003 e compará-lo ao revestimento de Cr (III), no mesmo substrato metálico. As técnicas empregadas foram polarização potenciodinâmica anódica, espectroscopia de impedância eletroquímica, microscopia eletrônica de varredura e mapeamento por espectroscopia de energia dispersiva. Utilizou-se um planejamento experimental 2³, no qual as variáveis foram velocidade de imersão, tempo de repouso após imersão e emersão na solução sol-gel à base de óxido de nióbio (razões molares n/n ácido cítrico/etilenoglicol 1:4, ácido e o complexo amoniacal de nióbio 10:1). Registrou-se uma tendência nas superfícies de respostas estudadas, sugerindo que em 5 min de imersão e emersão e na velocidade de 18 cm/min, o filme gerado apresenta uma maior resistência à corrosão. Os resultados de impedância eletroquímica e polarização potenciodinâmica anódica mostraram que o filme de óxido de nióbio apresenta maior resistência à corrosão que o revestimento utilizado industrialmente. Sendo assim, esse novo tratamento de superfície torna-se uma opção de substituição do revestimento a base de Cr (III).

The process of aluminum anodizing forms an oxide layer constituted of nanotubes where it is possible to insert compounds, amongst these are the pigments and dyes. This study has as its main aim to study the behavior of aluminum alloy 6000, anodized and dyed with monolite red in Na2SO4 0.5 mol L-1 and pH = 4. The techniques employed were: anodic potentiostatic polarization, open circuit potential, chemometry, polarization resistance and optical micrograph. The factorial planning was proposed using four variables (anodizing time, current density, electrolyte concentration, and dye), the response to the planning was the charge transfer resistance. Polarization curves revealed that the anodized and dyed aluminum samples are much more resistant than the non-anodized aluminum. Optical microscopy analyses demonstrated that the dissolution of dye occurs in the solution, but not enough to break the film. As the main result, efficient coloring of aluminum parts was verified with reduction in costs in relation to the energy employed in the process, associated to reduction in time spent for the anodizing process, which makes it suitable to increase industrial production of dyed aluminum parts.

Paint durability is directly linked to the efficiency of the substrate pre-treatment system. The objective to treat the carbon steel surface prior to painting is to turn the unstable metal surface into a stable surface one, an inert base to receive the paint. This is the main function of the phosphatization processes, which enables good paint adherence and prevents the development of corrosion processes. The demand for cleaner technologies, with lower residue generation, makes the phosphatization an unappealing method, and in this context the use of nanoceramics is an alternative to phosphate conversion layers. The objective of this study is to form a protection film which employs an organic molecule together with the zircon oxide, forming a layer which is able to anchor paint and increase the carbon steel resistance to corrosion. The treatment process conditions were established through the factorial planning, and the samples evaluated through the electrochemical impedance spectroscopy, scanning electronic microscopy and energy dispersive analysis. After comparing results of the electrochemical evaluation of the coating proposed with the iron and zinc phosphate coatings, it was possible to see that the film formed presented better corrosion resistance properties.

Recently, use of biodiesel as a diesel substitute has increased significantly. Currently, the biodiesel value added to diesel in Brazil is 10%. To maintain biodiesel quality during storage, antioxidants must be added. The most commonly used antioxidants are synthetic compounds. Due to the diversity of low cost agro-industrial waste with antioxidant activity, including cereal and fruit derivatives, several research studies reported the use of these waste materials as antioxidants. Barley waste (RCV) contains α-tocopherol (vitamin E), which acts as an antioxidant. Thus, this paper aims to investigate the use of RCV and citric acid as antioxidants in biodiesel. The conditions were optimized for the extraction and application of RCV in biodiesel (methyl ester soybean oil) using a 3² factorial design. RCV extracts were added during biodiesel production, which eliminates steps and improves the process. The antioxidant activity was evaluated using an accelerated oxidation method. Addition of RCV (11 g L–1) led to an induction time of 5.76 ± 0.11 h. However, addition of a blend of natural antioxidants [RCV (11 g L–1) and citric acid (0.1% w/v)] led to an increased induction time of 14.67 ± 2.10 h, which was attributed to the synergistic effect of the antioxidants.

The adsorption of organic substances in metals and in different media has been attributed to different effects, such as the carbon chain size, type or number of heteroatom in the molecule structure, reactivity, the steric effect, among others. The objective of this work is to study the electrochemical indole behavior for AISI 430 stainless steel (SS), when changing the study media from H2SO4 1 mol L-1 to HCl 1 mol L-1. The experimental techniques used are as follows: the open-circuit potential, anodic and cathodic potentiodinamic polarization, electrochemical impedance spectroscopy, optical microscopy and scanning electron microscopy. These results suggest that the adsorption of indole in the presence of SO4-2 is lower than in the medium containing Cl-, which is justified by the indole action as a weak acid, because it has only a single pair of electrons, which is displaced and takes part in the π-electron aromatic system; thus the first step of the indole reaction in acid media is the protonation and generation of an indole cation.

As moléculas auto-organizáveis (SAM - Self Assembly Monolayer) são inibidoras de corrosão, devido à capacidade de se organizarem sobre superfícies formando filmes finos. A SAM apresenta elevada afinidade pelo óxido formado sobre o alumínio, porém as interações entre a camada de óxido e as SAM nem sempre são satisfatórias, pois o óxido formado na superfície apresenta heterogeneidades, que interferem na formação do filme de SAM. O objetivo desse trabalho foi estudar a proteção à corrosão do alumínio AA 2024-T3 associada ao SAM, após tratamento com desengraxante alcalino. A caracterização eletroquímica foi realizada por espectroscopia de impedância eletroquímica e polarização potenciodinâmica anódica em meio de Na2SO4 0,5 mol. L-1 em pH 4,0. A morfologia superficial foi investigada por microscopia óptica. Os resultados mostraram que as SAM promoveram maior proteção do alumínio, quando este foi pré-tratado com o desengraxante. Self-assembly molecules (SAM - Self Assembly Monolayer) are corrosion inhibitors, due to their capacity to organize on surfaces, forming thin films. SAM presents a high affinity to aluminum oxide. However, the interactions between the oxide layer and SAM are not always satisfactory; therefore the oxide formed on the surface presents heterogeneities that hinder SAM film formation. The aim of this work was to study the corrosion protection of aluminum AA 2024-T3 associated with SAM, after treatment with alkaline degreasing. The electrochemical characterization was carried out by electrochemical impedance spectroscopy and anodic potentiodynamic polarization in Na2SO4 0,5 mol.L-1 in pH 4,0. The superficial morphology was investigated by optic microscopy. The results showed that SAM promoted greater aluminum protection when this was pretreated with degreasing.

Antioxidants are an alternative to prevent or retard biofuel degradation. This study assessed the oxidative stability of biodiesel B100, made from soybeans, in the presence of three synthetic antioxidants, butylhydroxyanisole (BHA), terbutylhydroquinone (TBHQ) and butylhydroxytoluene (BHT), pure or in mixture, from the simplex-centroid design. Results revealed that when the three oxidants were employed separately, as well as the ternary mixture, they presented induction period over 6 h, at 110 °C, being in accordance with specifications of the norm EN1412. Besides that, depending on the temperature, the BHA, TBHQ and BHT oxidants act in different ways, highlighting that BHA and TBHQ presented higher efficiency in the prevention of the oxidative process of the biofuel B100.

O uso de combustíveis fósseis está ameaçado pela sua possível escassez, sendo necessário a busca por alternativas ecológicas para atender a demanda de energia. Uma alternativa limpa e renovável é a utilização do gás hidrogênio, um combustível ecologicamente correto. Neste trabalho o hidrogênio obtido por eletrólise do ácido fórmico, hidróxido de sódio e glicerina tem como objetivo minimizar o consumo energético e possibilitar a utilização da glicerina, que é um subproduto da produção de biodiesel, como catalisador da produção de gás hidrogênio. Utilizou-se um planejamento fatorial 23 para avaliar a melhor concentração das substâncias em relação ao número de mol de hidrogênio produzido. Foram empregadas as técnicas eletroquímicas de potencial de circuito aberto, polarização potenciodinâmica catódica e curvas cronoamperométricas. E para análise da superfície do eletrodo de trabalho foi utilizada a microscopia eletrônica de varredura. Observou-se que é possível produzir hidrogênio utilizando soluções combinadas de ácido fórmico, hidróxido de sódio e glicerina, e substituir o eletrodo de platina pelo de aço inoxidável 254.

A preocupação mundial com a emissão de dióxido de carbono à atmosfera terrestre tem levado a exigências ambientais mais severas, e provocado o aumentado de estudos de geração de energias renováveis e menos poluentes, como por exemplo, o gás hidrogênio. Este trabalho tem como objetivo estudar a produção do gás hidrogênio via eletrólise da solução aquosa de ácido fórmico 3 mol L-1 , utilizando como eletrodos a platina, latão e cobre. As técnicas empregadas neste trabalho foram potencial de circuito aberto, polarização potenciodinâmica catódica e microscopia óptica. Os resultados obtidos mostram que os corpos de prova de latão lixados com lixas de SiC #320 apresentaram os maiores valores de densidade de corrente catódica, consequentemente maior produção de gás hidrogênio.

As distribuidoras de combustíveis utilizam containers de aço inoxidável para o armazenamento de biocombustíveis, entretanto, na literatura, há poucos relatos sobre os aspectos corrosivos desse aço em biodiesel. O objetivo desse trabalho é estudar o comportamento corrosivo do aço inoxidável austenítico 304 na presença de biodiesel, não lavado e lavado com soluções aquosas de ácido cítrico, oxálico, acético e ascórbico 0,01 mol L-1e comparar com os resultados obtidos para o cobre (ASTM D130). Empregaram-se técnicas como: espectrometria de absorção atômica (EAA) e microscopia óptica (MO). Os resultados de EAA mostraram uma baixa taxa de corrosão para o aço inoxidável, os elementos de liga estudados foram Cr, Ni e Fe, a maior taxa observada foi para o cromo, 1,78 ppm/dia em biodiesel não lavado ou lavado. As MO do aço 304, quando comparados com as do cobre, comprovaram a baixa taxa de corrosão para o sistema aço 304/biodiesel, entretanto comprovaram que, tanto o aço 304, quanto o cobre, sofrem corrosão em amostras de biodiesel. Fuel distribution uses 304 stainless steel containers for the storage of biofuels, however, there are few reports in the literature about the corrosive aspects this steel in biodiesel. The objective of this research is to study the corrosive behavior of 304 austenitic stainless steel in the presence of biodiesel, unwashed and washed, with aqueous solutions of citric, oxalic, acetic and ascorbic acids 0,01 mol L-1, and compare with results obtained for the copper (ASTM D130). The employedtechniques were: atomic absorption spectrometry (AAS) and optical microscopy (OM). The results of EAA showed a low rate of corrosion for the stainless steel, the alloys elements studied were Cr, Ni and Fe, the highest rate was observed for the chrome, 1.78 ppm / day in biodiesel with or without washing. The OM of the 304 steel, when compared with that of copper, has a low corrosion rate in the 304 steel/biodiesel system. Not with standing, this demonstrates that not only the 304 steel, but also the copper, corrodes in biodiesel.